xref: /netbsd-src/sys/arch/powerpc/include/fenv.h (revision d909946ca08dceb44d7d0f22ec9488679695d976)
1 /*	$NetBSD: fenv.h,v 1.1 2015/12/20 16:23:14 christos Exp $	*/
2 
3 /*-
4  * Copyright (c) 2004-2005 David Schultz <das@FreeBSD.ORG>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  *
28  * $FreeBSD: head/lib/msun/powerpc/fenv.h 226218 2011-10-10 15:43:09Z das $
29  */
30 
31 #ifndef	_POWERPC_FENV_H_
32 #define	_POWERPC_FENV_H_
33 
34 #include <sys/stdint.h>
35 
36 #ifndef	__fenv_static
37 #define	__fenv_static	static
38 #endif
39 
40 typedef	uint32_t	fenv_t;
41 typedef	uint32_t	fexcept_t;
42 
43 /* Exception flags */
44 #define	FE_INEXACT	0x02000000
45 #define	FE_DIVBYZERO	0x04000000
46 #define	FE_UNDERFLOW	0x08000000
47 #define	FE_OVERFLOW	0x10000000
48 #define	FE_INVALID	0x20000000	/* all types of invalid FP ops */
49 
50 /*
51  * The PowerPC architecture has extra invalid flags that indicate the
52  * specific type of invalid operation occurred.  These flags may be
53  * tested, set, and cleared---but not masked---separately.  All of
54  * these bits are cleared when FE_INVALID is cleared, but only
55  * FE_VXSOFT is set when FE_INVALID is explicitly set in software.
56  */
57 #define	FE_VXCVI	0x00000100	/* invalid integer convert */
58 #define	FE_VXSQRT	0x00000200	/* square root of a negative */
59 #define	FE_VXSOFT	0x00000400	/* software-requested exception */
60 #define	FE_VXVC		0x00080000	/* ordered comparison involving NaN */
61 #define	FE_VXIMZ	0x00100000	/* inf * 0 */
62 #define	FE_VXZDZ	0x00200000	/* 0 / 0 */
63 #define	FE_VXIDI	0x00400000	/* inf / inf */
64 #define	FE_VXISI	0x00800000	/* inf - inf */
65 #define	FE_VXSNAN	0x01000000	/* operation on a signalling NaN */
66 #define	FE_ALL_INVALID	(FE_VXCVI | FE_VXSQRT | FE_VXSOFT | FE_VXVC | \
67 			 FE_VXIMZ | FE_VXZDZ | FE_VXIDI | FE_VXISI | \
68 			 FE_VXSNAN | FE_INVALID)
69 #define	FE_ALL_EXCEPT	(FE_DIVBYZERO | FE_INEXACT | \
70 			 FE_ALL_INVALID | FE_OVERFLOW | FE_UNDERFLOW)
71 
72 /* Rounding modes */
73 #define	FE_TONEAREST	0x0000
74 #define	FE_TOWARDZERO	0x0001
75 #define	FE_UPWARD	0x0002
76 #define	FE_DOWNWARD	0x0003
77 #define	_ROUND_MASK	(FE_TONEAREST | FE_DOWNWARD | \
78 			 FE_UPWARD | FE_TOWARDZERO)
79 
80 #ifndef _KERNEL
81 __BEGIN_DECLS
82 
83 /* Default floating-point environment */
84 extern const fenv_t	__fe_dfl_env;
85 #define	FE_DFL_ENV	(&__fe_dfl_env)
86 
87 /* We need to be able to map status flag positions to mask flag positions */
88 #define	_FPUSW_SHIFT	22
89 #define	_ENABLE_MASK	((FE_DIVBYZERO | FE_INEXACT | FE_INVALID | \
90 			 FE_OVERFLOW | FE_UNDERFLOW) >> _FPUSW_SHIFT)
91 
92 #ifndef _SOFT_FLOAT
93 #define	__mffs(__env)	__asm __volatile("mffs %0" : "=f" (*(__env)))
94 #define	__mtfsf(__env)	__asm __volatile("mtfsf 255,%0" : : "f" (__env))
95 #else
96 #define	__mffs(__env)
97 #define	__mtfsf(__env)
98 #endif
99 
100 union __fpscr {
101 	double __d;
102 	struct {
103 		uint32_t __junk;
104 		fenv_t __reg;
105 	} __bits;
106 };
107 
108 __fenv_static inline int
109 feclearexcept(int __excepts)
110 {
111 	union __fpscr __r;
112 
113 	if (__excepts & FE_INVALID)
114 		__excepts |= FE_ALL_INVALID;
115 	__mffs(&__r.__d);
116 	__r.__bits.__reg &= ~__excepts;
117 	__mtfsf(__r.__d);
118 	return (0);
119 }
120 
121 __fenv_static inline int
122 fegetexceptflag(fexcept_t *__flagp, int __excepts)
123 {
124 	union __fpscr __r;
125 
126 	__mffs(&__r.__d);
127 	*__flagp = __r.__bits.__reg & __excepts;
128 	return (0);
129 }
130 
131 __fenv_static inline int
132 fesetexceptflag(const fexcept_t *__flagp, int __excepts)
133 {
134 	union __fpscr __r;
135 
136 	if (__excepts & FE_INVALID)
137 		__excepts |= FE_ALL_EXCEPT;
138 	__mffs(&__r.__d);
139 	__r.__bits.__reg &= ~__excepts;
140 	__r.__bits.__reg |= *__flagp & __excepts;
141 	__mtfsf(__r.__d);
142 	return (0);
143 }
144 
145 __fenv_static inline int
146 feraiseexcept(int __excepts)
147 {
148 	union __fpscr __r;
149 
150 	if (__excepts & FE_INVALID)
151 		__excepts |= FE_VXSOFT;
152 	__mffs(&__r.__d);
153 	__r.__bits.__reg |= __excepts;
154 	__mtfsf(__r.__d);
155 	return (0);
156 }
157 
158 __fenv_static inline int
159 fetestexcept(int __excepts)
160 {
161 	union __fpscr __r;
162 
163 	__mffs(&__r.__d);
164 	return (__r.__bits.__reg & __excepts);
165 }
166 
167 __fenv_static inline int
168 fegetround(void)
169 {
170 	union __fpscr __r;
171 
172 	__mffs(&__r.__d);
173 	return (__r.__bits.__reg & _ROUND_MASK);
174 }
175 
176 __fenv_static inline int
177 fesetround(int __round)
178 {
179 	union __fpscr __r;
180 
181 	if (__round & ~_ROUND_MASK)
182 		return (-1);
183 	__mffs(&__r.__d);
184 	__r.__bits.__reg &= ~_ROUND_MASK;
185 	__r.__bits.__reg |= __round;
186 	__mtfsf(__r.__d);
187 	return (0);
188 }
189 
190 __fenv_static inline int
191 fegetenv(fenv_t *__envp)
192 {
193 	union __fpscr __r;
194 
195 	__mffs(&__r.__d);
196 	*__envp = __r.__bits.__reg;
197 	return (0);
198 }
199 
200 __fenv_static inline int
201 feholdexcept(fenv_t *__envp)
202 {
203 	union __fpscr __r;
204 
205 	__mffs(&__r.__d);
206 	*__envp = __r.__d;
207 	__r.__bits.__reg &= ~(FE_ALL_EXCEPT | _ENABLE_MASK);
208 	__mtfsf(__r.__d);
209 	return (0);
210 }
211 
212 __fenv_static inline int
213 fesetenv(const fenv_t *__envp)
214 {
215 	union __fpscr __r;
216 
217 	__r.__bits.__reg = *__envp;
218 	__mtfsf(__r.__d);
219 	return (0);
220 }
221 
222 __fenv_static inline int
223 feupdateenv(const fenv_t *__envp)
224 {
225 	union __fpscr __r;
226 
227 	__mffs(&__r.__d);
228 	__r.__bits.__reg &= FE_ALL_EXCEPT;
229 	__r.__bits.__reg |= *__envp;
230 	__mtfsf(__r.__d);
231 	return (0);
232 }
233 
234 #if defined(_NETBSD_SOURCE) || defined(_GNU_SOURCE)
235 
236 /* We currently provide no external definitions of the functions below. */
237 
238 static inline int
239 feenableexcept(int __mask)
240 {
241 	union __fpscr __r;
242 	fenv_t __oldmask;
243 
244 	__mffs(&__r.__d);
245 	__oldmask = __r.__bits.__reg;
246 	__r.__bits.__reg |= (__mask & FE_ALL_EXCEPT) >> _FPUSW_SHIFT;
247 	__mtfsf(__r.__d);
248 	return ((__oldmask & _ENABLE_MASK) << _FPUSW_SHIFT);
249 }
250 
251 static inline int
252 fedisableexcept(int __mask)
253 {
254 	union __fpscr __r;
255 	fenv_t __oldmask;
256 
257 	__mffs(&__r.__d);
258 	__oldmask = __r.__bits.__reg;
259 	__r.__bits.__reg &= ~((__mask & FE_ALL_EXCEPT) >> _FPUSW_SHIFT);
260 	__mtfsf(__r.__d);
261 	return ((__oldmask & _ENABLE_MASK) << _FPUSW_SHIFT);
262 }
263 
264 static inline int
265 fegetexcept(void)
266 {
267 	union __fpscr __r;
268 
269 	__mffs(&__r.__d);
270 	return ((__r.__bits.__reg & _ENABLE_MASK) << _FPUSW_SHIFT);
271 }
272 
273 #endif /* _NETBSD_SOURCE || _GNU_SOURCE */
274 
275 __END_DECLS
276 #endif
277 
278 #endif	/* !_POWERPC_FENV_H_ */
279